1. Technical Field
The present disclosure generally relates to illuminating systems and controlling method thereof, and particularly, to a light emitting diode (LED) illuminating system and a controlling method thereof.
2. Description of Related Art
Nowadays, most of the LED illuminating systems are supplied with an alternating current. Generally, the alternating current, which is supplied to the LED illuminating system, is firstly converted into a low-voltage direct current by an AC/DC (alternating current to direct current) converter and successively converted into a constant direct current by a DC/DC (direct current to direct current) converter. Finally the constant direct current is supplied to the LED illuminating system. However, the AC/DC converter usually has a predetermined and invariable output voltage which cannot vary according to different working temperatures around the LED illuminating system. The DC/DC converter requires different voltages due to different temperatures so that the DC/DC converter can output the constant direct current to the LED lamp. As such, when the working temperature changes, the predetermined voltage supplied from the AC/DC converter to the DC/DC converter should be more or less than the predetermined voltage that the AC/DC converter will supply to the DC/DC converter in the normal rated temperature; otherwise, an unsatisfied illuminating efficiency of the illuminating system occurs since the direct current supplied to the LED lamp by the DC/DC converter can no longer be constant.
Therefore, what is needed is an illuminating system and a controlling method of the illuminating system that overcome the described limitations.